We turn now to the shopping frenzy. The crowded stores tonight, and a sudden move by one of america's biggest banks to protect millions of debit card holders who shop at target. A new spending cap in the wake of a security breach. Abc's aditi roy with that story. Reporter: It's the busiest shopping weekend of the year. And more fallout from the security breach on credit and debit cards at target stores nationwide. Now the largest bank in the u.S., Jpmorgan chase, says it is putting limits on debit card holders who shopped at target between november 27th and DECEMBER 15th. That's when store officials say as many as 40 million accounts were compromised. Nearly 2 million chase debit card holders who shopped at target stores during that time are being told today they can only withdraw $100 on their debit cards on any one day and limit total purchases to $300 a day. Chase said this action is a precaution to protect customer accounts from criminal activity. Chase is the grinch that stole christmas from families all across america. And the reality is, they're doing it to protect themselves and they're holding people's moneys hostage. Reporter: In a dramatic move, the bank says it is opening up more than a third of its branches today to issue new cards to card holders effected by the hacking scheme. For its part, target is trying to soften the blow, offering 10% discounts on all items this weekend. A target spokesman telling abc news, the company has activated even more fraud protection and is answering customer questions. Adding, "our customers need to continue to be vigilant, and we are working to help them report issues." It's an all-out effort to salvage a holiday nightmare. Aditi roy, abc news, los angeles.

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